The increased power requirements of today's computer systems leads to a proportionately increased heat load. Generally speaking, the historically installed heating, ventilating, and air conditioning (HVAC) systems are not capable of keeping up with this growth. Rear door heat exchangers address this problem by cooling the air exhausted from rack mounted systems. These heat exchangers are primarily viewed as local cooling devices designed to treat particular hot spots. In particular, the heat exchangers absorb energy from the hot air flow from the computer system and transfer it into water. However, cooling of the air around the rack mounted system can also be viewed as a heating process from the point of view of the cooling cycle. This aspect becomes important if a site operates with combined cooling, heating, and power generation (trigeneration or “CCHP”) where the energy from the return flow of the cooling cycle becomes part of a larger energy cycle with appropriate measurement and control requirements.
One drawback of existing rear door heat exchangers is the need for an external monitoring system to detect failures. These failures may include, for example, leakages and overheating of the equipment in the rack. Both events can cause serious damage to the equipment and environment, and therefore, must be detected as soon as possible. Because no human operator is present to guard against device failures in typical operating environments, these failures often go undetected for extended periods of time. Thus, although there is a need for remote “alerts” in case of failures, existing rear door heat exchanger systems do not provide such a feature.
Based on the foregoing, there exists a need for an improved system and method for measuring and monitoring heat quantity in rack mounted computer systems. There is also a need for an improved system and method for detecting failures and initiating an alert or other appropriate action in response to the detection of a failure.